Glucose Induces Thylakoid Formation and Upregulates Green Pigment Contents in Complete Dark Culture of the Angiosperm Pachiramacrocarpa

In addition to angiosperms, most plants are able to synthesize chlorophyll (Chl)-generating green tissues in total darkness. In this study, 140 plants of the angiosperm Pachira macrocarpa were divided into five groups. Among them, one group was grown for 2 weeks under natural light conditions, whereas the others were grown in complete darkness (0 μmol m−2 s−1). Dark-grown plants were then treated with 0~6% glucose for another 8 weeks. The budding and greening ratios, ultrastructure of chloroplasts (ChlPs) of newly developed leaves, and green pigment contents of pre-illuminated mature and young leaves, and totally dark-grown newly developed leaves were measured. Results showed that glucose inhibited the budding and promoted the greening of newly developed leaves. Pre-illuminated mature and young leaves were able to synthesize green pigments during the 2 weeks of dark adaption. Dark-grown newly developed leaves contained high levels of green pigments at 2 and 3 weeks after budding. Green pigments of glucose-fed newly developed leaves had increased, whereas they had decreased in control leaves. In addition, ChlPs of dark-grown glucose-fed newly developed leaves contained both giant grana and prolamellar bodies (PLBs), usually found in shade plants and etiolated seedlings, respectively. The higher the glucose concentration was, the greater the numbers of grana, thylakoids, and PLBs. Glucose increased the green pigment contents and grana formation in newly developed leaves in a dark condition, and the mechanisms are discussed.

Study on the amount of chlorophyll content and leaf area of Robusta coffee plants with shade trees and fertilizer application in Hanakau Sukau West Lampung

Coffee is one of the most important plantation crops in Indonesia. Coffee has high economic value, significantly increasing income, especially in West Lampung district, Lampung province. Coffee production in this area reaches 954 kg ha. Some subdistricts can produce more than 1,000 kg ha-1 year -1, and some have only reached 500 kg ha-1 year -1 This research was conducted from June to November 2020, to get the effect of shade plants and the effect of types of fertilizers on the productivity of robusta coffee and their interaction on robusta coffee production. The results showed that the amount of chlorophyll content of robusta coffee leaves was not influenced by shade and fertilization, and the interaction between fertilization and shade trees had an effect on leaf surface area.

Effect of natural male and female (sex ratio) on nutmeg (Myristica fragrans) production on Maluku

The composition of males and females is very influential on the productivity of nutmeg plants. This research aimed to get the composition of male, female, and shade types related to the productivity of the nutmeg plant in the center of nutmeg in Maluku. Nested Design Three-Factor. Production centers are divided: Large Island, Medium Island and Small Island, determined as Factor A. Data on the number of trees Ratio male: female as factor B (B1 = ratio <1:10); (B2 = ratio 1:10 - 1:15); and (B3 = ratio> 1:20). Minimum of five female nutmeg samples for observation of production in a layered (Proportional Stratified Random Sample) harvest season in a year as a replication, namely Harvest I; Harvest II; and Harvest III. The results showed that the natural sex ratio of nutmeg was 1:10 in Small Island, Medium Island, and Big Island. The average productivity of nutmeg was 1,494, 1,465, and 1,296 fruit/tree/year, respectively. The farming system in Small Island was a monoculture of 100% shade plants, while in Medium and Big Island, the farming system was 33% - 50% shade plants and 50% - 67% other perennial crops.

Differences in leaf area, trichome density, and xylem structure between the two types of Theobroma cacao l. cultivation: With or without shade plants

This study aimed to analyze the structure and density of non-glandular trichomes and the area of cocoa leaves, and the differences of xylem vessel structures on various shade tree composition. The leaf area and length, and trichomes were observed. The xylem vessel structure was observed from the root system. The result showed the area of cocoa plots without shade tree has more varied leaves size, in which upper canopy was smaller than the bottom. The area with various shade had a relatively equal size between the upper and the lower of the canopy. The three stellate-shaped non-glandular trichomes were found on the leaf venations only with the density in two plots increased with time. The xylem width area to the whole root width area ratio (k) in various shade trees was lower (k= 0.641) than that of without shade trees (k= 0.718). The higher k values indicated xylem structure without the shade tree had more xylem cells, and the pores was smaller compared to the plot with various shade trees.

The specific leaf area of forest species subjected to different degrees of shading did not differ when detached and full leaflets were compared

Studies of forest species under different environmental conditions are essential for enhancing our understanding of plant-environment relationships. Different light conditions interfere with the production of seedlings within forests, and this interference can be verified by assessing leaf area. However, several species have leaf compound that often contain numerous leaflets, which makes the direct measurement of leaf area difficult. This leads researchers to question whether these types of leaves should be separated for analysis or measured whole. Thus, the aim of this study was to analyse specific leaf area in whole leaves and detached leaflets of six forest species subjected to different levels of shading. The forest species assessed all produced compound leaves and included Schinus terebinthifolius Raddi (aroeira), Schinopsis brasiliensis Engl. (braúna), Dalbergia nigra (Vell.) Fr. All. ex Benth. (jacaranda-da-bahia), Chorisia speciosa A. St.-Hil (paineira), Caesalpinia peltophoroides Benth (sibipiruna) and Plathymenia reticulata Benth (vinhático). Each species was subjected to six different degrees of shading: 0% (full sun); 20; 40; 60; 80 and 90%. Sombrite netting was used to shade plants. The analysis of the specific leaf area was performed using two different methods, which included the analysis of separate leaflets and whole leaves. To analyse leaflet area,50 leaflets per plant were assessed three times, and six plants per treatment were assessed. To assess whole leaves, data were obtained from the whole leaves of six plants per treatment. This process was repeated for all aforementioned species. Data obtained from both analysis methods indicated that all species assessed were similarly affected by shade, and leaf area varied according to the level of shading. This similarity of data demonstrates that, for these species, it is not necessary to use complex methods to obtain specific leaf area measurements. Thus, determining specific leaf by measuring the entire leaf provides results that did not statistically differ from those obtained by measuring individual leaflets.

Intensitas Cahaya dan Efisiensi Fotosintesis pada Tanaman Naungan dan Tanaman Terpapar Cahaya Langsung

Plant growth and productivity influenced by light. Sunlight activates light-dependent reactions or LDR and Calvin cycle or LIR in plant. Different light intensity induce change of LDR and LIR. Adaptation through efficiency of photon absorption, regulation of photosystem II - photosystem I, and carbon fixation can make photosynthesis efficiently. This paper aims to review research on photosynthesis mechanism in sun and shade plants. Alteration of light absorption in plants produce morphological and physiological adaptations. Plant adaptation mechanism use sieve effect, light channeling, and acclimatization. Distribution of chlorophyll in both types of plants changed the photosynthesis photon flux density. Propagation and distribution of light needed through vacuoles to minimize the distance on electron transport chain. Physiological acclimatization accelerates by changing the composition of chlorophyll and PSII / PSI ratio. Shade plants have a high ratio PS II / PSI and high ratio chlorophyll a / b to increase the light-harvesting complex and make photosynthesis efficiently.

Shade-avoidance responses become more aggressive in warm environments

When exposed to neighbour signals, competitive plants increase the growth of the stem to reduce the degree of current or future shade. Plants can experience similar neighbour cues under different weather conditions and the aim of this work is to investigate the impact of daily average temperature and irradiance and thermal amplitude on the magnitude of shade-avoidance responses in Arabidopsis thaliana. For this purpose, we first generated a growth database and elaborated under controlled conditions a model that predicts hypocotyl growth during the photoperiod as a function of the light-modulated activity of the main photo-sensory receptors (phytochromes A and B, cryptochromes 1 and 2), temperature-modulated activity of phytochrome B and an independent temperature input. Thermal amplitude (lower temperatures during the morning and afternoon that at midday) reduced growth of genotypes with normally fast morning growth, and this effect was incorporated to the model. Thermal amplitude also decreased the abundance of the growth-promoting transcription factor PHYTOCHROME-INTERACTING FACTOR 4. The model predicted growth in the field through different seasons with reasonable accuracy. Then, we used the model in combination with a worldwide dataset of current and future whether conditions. The analysis predicted enhanced shade-avoidance responses as a result of higher temperatures due to the geographical location or global warming. Irradiance and thermal amplitude had no effects. These trends were also observed for our local growth measurements. We conclude that, if water and nutrients do not become limiting, warm environments enhance the shade avoidance response.

Diversity of Arthropods and Parasitic Nematodes Population in Intercropping Patterns of Robusta Coffee

Shade plants affect the microclimates around the plants which directly affect the population of arthropods, especially insects. Therefore, this research was needed to analyze the diversity and role composition of insects in Robusta coffee plantations based on different intensity of shade plants. Samplings of insects and parasitic nematodes were conducted in intercropping patterns of Robusta coffee namely mixed intercropping patterns, coffee-pepper intercropping patterns and coffee-banana intercropping patterns. In each intercropping pattern of Robusta coffee, samplings were conducted as much as ten plants using random sampling. Data analysis was done by calculating the Shannon-Wiener diversity index (H') and evenness index (E). The results showed that diversity index in all Robusta coffee intercropping patterns were < 3, indicating that the diversity of insects in all intercropping patterns was relatively. Insect diversity in coffee-pepper inter- cropping pattern is found higher than the one in either mixed intercropping pattern or coffee-banana intercropping patterns. Out of those intercropping patterns, insects from Formicidae family of Hymenoptera order was found to be the most dominant insects. The composition of insects in all of those three intercropping patterns has been mainly dominated by insects from the family of Formicidae and Hymenoptera order since they are natural enemy insects. Pratylenchus coffeaehas been confirmed as the most dominant nematode species in the three Robusta coffee intercropping pattern. P. coffeae had the highest population average of 3279 in coffee-pepper intercropping pattern.

Pengaruh Pembayangan terhadap Kenyamanan Termal pada Rumah Tinggal di Perumahan Bukti Baruga Antang Makassar

Abstrak_ Penelitian ini dilakukan dengan mengukur kenyamanan termal alami dan mengetahui seberapa besar pengaruh tanaman peneduh terhadap kenyamanan termal alami didalam rumah tinggal. Rumah tinggal dikelompokkan menjadi dua kelompok yaitu rumah tinggal yang ada tanaman peneduh dan rumah tinggal yang tidak ada tanaman peneduh. Data pengukuran statis dilakukan dengan beberapa variabel kenyamanan berupa suhu, kelembaban, dan kecepatan angin kemudian diukur menggunakan alat HOBO temp/RH logger dengan waktu pengukuran dari pukul 06.00-18.00 WITA. Hasil penelitian menunjukkan bahwa rata-rata temperatur tertinggi untuk rumah tinggal yang ada tanaman peneduh 30,2°C dan rumah tinggal yang tidak ada tanaman peneduh 31,3°C. Kemudian rata-rata kelembaban tertinggi rumah tinggal yang ada tanaman peneduh 73% dan yang tidak ada tanaman peneduh 73%, dengan ini kelembaban berada pada zona yang nyaman. Sedangkan hasil rata-rata 0,19 m/s untuk kecepatan angin tertinggi rumah tinggal yang tidak ada tanaman peneduh dan 0,65 m/s rumah tinggal yang ada tanaman peneduh. Hasil survey kenyamanan penghuni menunjukkan sebagian responden masih merasa nyaman namun tetap mengharapkan kondisi kenyamanan termal yang lebih sejuk lagi. Responden beradaptasi dengan kondisi lingkungannya dengan cara memilih pakaian yang nyaman dan tipis serta mengurangi kegiatan yang menimbulkan banyak keringat. Kata kunci : Kenyamanan Termal, Tanaman Peneduh, Rumah tinggal, Responden penghuni. Abstract_ This research was conducted by measuring natural thermal comfort and knowing how much influence the shade plants have on natural thermal comfort in the house. Dwellings are grouped into two groups namely dwellings with shade plants and dwellings with no shade plants. Static measurement data is carried out with several comfort variables in the form of temperature, humidity, and wind speed and then measured using a HOBO temp / RH logger tool with measurement time from 06.00-18.00 WITA. The results showed that the average highest temperature for houses with shade plants was 30.2 ° C and houses without shade plants were 31.3 ° C. Then the highest average humidity of residential houses with 73% shade plants and 73% without shade plants, with this humidity is in the comfort zone. While the average yield of 0.19 m / s for the highest wind speed of houses without shade plants and 0.65 m / s of shade houses. The results of the occupants comfort survey show that some respondents still feel comfortable but still expect cooler conditions of thermal comfort. Respondents adapt to environmental conditions by choosing comfortable and thin clothing and reducing activities that cause a lot of sweat. Keywords : Thermal Comfort, Shade Plants, Residential Houses, Resident Respondents